"I think the last time I touched an actual meta key was on a DECStation
keyboard in the early 90s"
What, no Windows keyboard for you?
I map the Windows-logo key to Meta, since it sure looks to me like the
meta keys I had I my old Sun SparcStations. Similarly, Apple keyboards
have an Apple-logo key that serves the same purpose. Note that both Emacs
and X11 have a separate modifier code for Alt and Meta.